NASA used its TETR-A
training satellite to relay voice, pictures, and telemetry data to
ground controllers as if it were real data coming from the
spacecraft. This way the controllers didn't have to know it was a
hoax; they thought they were running a real mission. [Bart
Sibrel]

There were two groups of people that dealt with telemetry during
Apollo. The operators of the MSFN
collected the radio signals from space and relayed them over land
lines to the Mission Control Center (MCC) where they were collated and
displayed. At MCC, the flight controllers interpreted the data and
made decisions affecting the mission.

Because of the design of the MSFN, a satellite was not required to
train the MCC controllers. Simulations were easy to set up. The
instructors simply disconnected the outlying stations from the MSFN
hub and substituted an equivalent stream of simulated data created by
their own ground equipment. The controllers at MCC didn't know or
care where the data came from. It was specifically designed this way
so that simulations would be indistinguishable from the real thing.

So Sibrel can argue it was possible for the ground controllers to
be fooled by simulated data. But it doesn't take a satellite to do
it.

MSFN Antennas must be precisely aimed, and a low earth orbit
satellite cannot mimic the sky position of a translunar spacecraft.

The MSFN operators absolutely can't be fooled by a satellite.
Their antennas must be precisely aimed, and a satellite doesn't follow
the same path in the sky as an outbound or inbound Apollo spacecraft.
They'd know. Their ability to locate the spacecraft in the sky is
nothing short of legendary. They took great pride in being able to
use the Doppler shift of the radio signal to determine the flight
path of the spacecraft. When compared later with flight records,
the MSFN ground station operators were proud to have observed motion
of the spacecraft due to such subtle effects as waste dumps and
sublimator operation.

As seen from earth, an Apollo spacecraft on a translunar
trajectory would always be in roughly the same direction as the moon.
But the TETR-A satellite was in a 172 × 294 mile (287 ×
490 km) orbit that required only 92 minutes to complete one
revolution. From a point on earth it would appear to streak across
the sky in a matter of minutes.

Mike Dinn, an Australian scientist who worked at the MSFN tracking
station in Australia, writes

"It [the TETR-A] had little more than a transponder and some
housekeeping telemetry and limited life. It wasn't really needed as
we had Lunar Orbiter and Surveyor spacecraft which were used from some
training."

If these people cannot be fooled by a satellite then they have to
be included in the conspiracy. But they can simply be told to pretend
to track a spacecraft and acquire signals from it. The TETR-A
satellite would be completely irrelevant.

So the TETR-A satellite is neither necessary to fool MCC
controllers nor sufficient to fool MSFN operators. This charge seems
to stem more from the conspiracists' knack for spinning a good yarn
than from an effort to formulate a plausible theory for how lunar
landings might be falsified.

Sibrel doesn't elaborate on how he knows the TETR-A was still
orbiting well into 1972, despite NASA's claim that it de-orbited and
burned up on April 28, 1968.

Objects already in orbit pose a collision hazard to launches.
Spacefaring nations habitually track spaceborne objects that might
interfere with their launches. So if NASA claims its satellite burned
up, but it was really still up there, the Soviets would have seen it.
It's not as easy to hide a satellite as Sibrel believes.